| Description |
%function angles=satang4(strSys1,latA,longA,longsat,strSys2,latB,longB)
%calculation of satellite angles: elevation, azimuth, and also relative azimuth and baseline orientation if input data
%belongs to two sites
%Sources:
%Digital satellite communications, 2nd Ed. Author Tri Ha, for satellite azimuth and elevation calculation
%http://williams.best.vwh.net/avform.htm#Rhumb for distance and relative azimuth between two coordinates
%tested using various satellites and earth stations, and using http://www.sfwx.com/softworks/geoBearing.html and
%http://www.geocities.com/senol_gulgonul/linkbudget/azel.html
%differences are in part due to the selection of the earth radius and orbit heigth values, and also to possible mistakes in the
%code...please point them out
%INPUTS
%strSys1: string: 'E' for longitude in degrees east, 'W' for longitude in degrees West. no negative values
%strSys2: string: 'GC' for GREAT CIRCLE , 'RH' for RHUMB (CONSTANT AZIMUTH: recommended for site diversity purposes)
%latXX: latitude of site A or B. + north, - south
%longXX: longitude of site A and B: following strSys1.
%longsat: longitude of subsatellite point, E or W according to srtSys
%OUTPUTS
%angles: a structure containing:
% .elevation elevation angle to satelite,
% .azimuth azimuth to satelite
% .poltilt & poltilt_c feed rotation to compensate geographic position
%NOTE standing behind the antenna,
%rotation is CLOCKWISE for a station
%located east of the satellite meridian,
%and ANTICLOCKWISE for a station west of
%the satellite meridian
%poltilt_c is more reliable than poltilt.
% .Az_AB true course, azimuth in the direction of site B (rhumb line, constant azimuth)
% .distance distance between the two sites
% .baselineorientation for site diversity, BOA acording to ITU-R P618-8 definition.
%EXAMPLE OF USE
%angles=satang4('E',-8.83,13.25,0) | angles=satang('E',-33.93,18.47,0)
%angles = |
% elevation: 71.2774 | elevation: 45.7078
% azimuth: 303.1005 | azimuth: 329.1038
%Meteosat satellite, cities of cape town and luanda.
%
%angles=satang4('E',6.4,360-76.4,304.5)
%angles =
% elevation: 64.3472
% azimuth: 106.2730 Intelsat 8A, city of medellin
%geographical constants
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